When he was seventeen, Su Nian met Lin Yu.
He is the top science student in his grade, handsome and gentle, and a bright young man among the crowd. She is a quiet and reserved ordinary girl in the liberal arts class. She is used to writing her thoughts in a light blue diary. Starting from the words "Hello, new classmate" on the day of class placement, they walked side by side through the dusk on Wutong Road, shared the afternoon sunshine in the library, and held hands on the rooftop to watch the most beautiful sunset in their lives.
The grandest encounter in youth is often caught off guard.
They spent the long night of their senior year together, made a promise to go to the north to see the snow, and put all their imaginations about the future into a hand-drawn map. Su Nian thought this was the beginning of eternity, but he didn't know that Lin Yu had been suffering a secret alone - congenital heart disease and the little time he had left.
Hiding it from her, he wrote all his reluctances into thirteen letters and drew all his regrets into a photo album. He used his last effort to mark all the places he wanted to go with her. Then at the end of that summer, I stopped at eighteen forever.
Many years later, Su Nian traveled through Beijing, Xiamen, Dali, and Tibet alone. She looked at the heavy snow, the sea, and the starry sky for him. She carried his name to every place he could not reach.
But every time I turned around, there was no one behind me.
Youth will end, but love will not. Some people stay at the age of seventeen forever, but spend their whole life living in another person's heart.
This is a story about meeting and parting. Gentle, restrained, with great staying power.